Quantitative assessment of swallowing in healthy adults

Swallowing has hitherto been evaluated during physical examination, radiologic barium studies, manometry, and cervical auscultation. Radiography principally demonstrates qualitative aspects of oral and pharyngeal function, whereas quantitative aspects have primarily been documented by manometry. To evaluate swallowing quantitatively, without using invasive methods or radiation, we have applied a combined test of water drinking, i.e., the Repetitive Oral Suction Swallow test (ROSS). The test provides reliable measurements of suction pressure, bolus volume, timing of important events in oral and pharyngeal swallow, and respiration. The test is described and results from 292 healthy, nondysphagic subjects are presented. We found a mean bolus volume of 25.6±8.5 ml during single swallow and 21.1±8.2 ml during stress (forced, repetitive swallow). During forced, repetitive swallow, the bolus volume was more strongly associated with suction time (r²=0.55) than with peak suction pressure (r²=0.04), indicating that suction time is more important than suction pressure in determining the bolus volume. The oral-pharyngeal transit time decreased: single swallow 0.56±0.36 sec, forced repetitive swallow 0.23±0.11 sec, as did the coefficient of variation (48% and 64%, respectively) indicating a more automatic neural process for pharyngeal function in forced, repetitive swallow. The postswallow respiration started with inspiration in 10% of studied individuals, but did not correlate with deviations in other variables in the test. Thus, postswallow inspiration must be considered as normal. The ROSS test offers a rapid and easy quantitative assessment of swallowing.     

Quantitative assessment of oral and pharyngeal function in Parkinson's disease

Oral and pharyngeal dysfunction is common in Parkinson's disease. To reveal the frequency of swallowing dysfunction and correlate swallowing dysfunction with locomotor disturbances, we studied 75 patients with Parkinson's disease staged I–IV according to the Hoehn and Yahr score. We assessed oral and pharyngeal swallow during optimal medication by a quantitative test of swallowing (the ROSS test) measuring the suction pressure, bolus volume, swallowing capacity, and time for important events in the swallowing cycle. We found abnormal results in 7/12 patients (58%) in stage 1 of the Hoehn and Yahr score, in 13/14 patients (93%) in stage 2, in 29/32 patients (91%) in stage 3, and in 16/17 patients (94%) in stage 4. Abnormal test results in stages, 1, 2, and 3 were seldom related to swallowing difficulties noticed by the patients. In advanced disease (Hoehn and Yahr stage 4), the abnormal results were often considerable, with swallowing difficulties obvious to the patient. Two of 17 patients coughed during or immediately after the test and 3/17 patients were unable to complete the test. The degree of swallowing disturbance increased during stress (forced, repetitive swallow). The Hoehn and Yahr score and the results in the ROSS test did not correlate, indicating that swallowing disturbances are due to nondopaminergic degeneration. Silent swallowing impairment may interfere with the nutrition and quality of life in Parkinson's disease, thus it is of interest to monitor this in clinical practice.     

Dysphagia in Stroke: A Prospective Study of Quantitative Aspects of Swallowing in Dysphagic Patients

This is a prospective study of 100 consecutive stroke patients. Within 24 h after stroke onset they were asked specifically about swallowing complaints and subjected to a clinical examination including neurologic examination, Mini-Mental test, and Barthel score. Dysphagic patients were examined with the repetitive oral suction swallow test (the ROSS test) for quantitative evaluation of oral and pharyngeal function at 24 h, after 1 week, and after 1 month. At 6 months, the patients were interviewed about persistent dysphagia. Seventy-two patients could respond reliably at 24 h after the stroke onset and 14 of these complained of dysphagia. Non-evaluable patients were either unconscious, aphasic, or demented. The presence of dysphagia was not influenced by age or other risk factors for stroke. Facial paresis, but no other clinical findings, were associated with dysphagia. Dysphagia 24 h after stroke increased the risk of pneumonia but did not influence the length of hospital stay, the manner of discharge from hospital, or the mortality. The initial ROSS test, during which the seated patient ingests water through a straw, was abnormal in all dysphagic stroke patients. One-third of the patients were unable to perform the test completely. Above all, dysfunction was disclosed during forced, repetitive swallow. All phases of the ingestion cycle were prolonged whereas the suction pressures, bolus volumes, and swallowing capacities were low. Abnormalities of quantitative swallowing variables decreased with time whereas the prevalences of swallowing incoordination and abnormal feeding-respiratory pattern became more frequent. After 6 months, 7 patients had persistent dysphagia. Five of these were initially non-evaluable because of unconsciousness, aphasia, or dementia.     

Food intake by maneuver; An extreme compensation for impaired swallowing

We report two young patients able to exist on exclusively oral intake despite an absent pharyngeal swallow response. Videofluoroscopic swallowing studies showed that both patients used a sequence of devised maneuvers rather than a coordinated pharyngeal swallow to move the bolus, protect the airway, and open the upper esophageal sphincter during bolus ingestion. We conclude that it is possible for young, highly motivated individuals to maintain oral intake despite ablation of neurologic elements crucial for the normal swallow response.     

Quantitative aspects of swallowing in an elderly nondysphagic population

The prevalence of swallowing impairment increases with age and is a major health care problem in the elderly. It has been assumed that age-related changes in nerves and muscles hamper muscle strength and coordination of swallowing. However, it is unclear what impairment is related to primary aging and what is the consequence of diseases prevalent in the elderly (secondary aging). In order to quantify swallowing in nondysphagic elderly we used the noninvasive ROSS (Repetitive Oral Suction Swallow) test. A total of 53 individuals aged 76±5 years (mean±SD) were examined. We found that the nondysphagic elderly demonstrated significant differences compared with young individuals in 10 of 17 measured variables, i.e., decreased peak suction pressure, increased frequency of multiple swallows after one ingestion, increased frequency of polyphasic laryngeal movements, increased frequency of inspiration after swallowing, and increased frequency of coughing during or after swallowing. Therefore, primary aging mainly seems to influence coordination of swallowing, but oral and pharyngeal swallow per se seem to be unaffected.     

Common Medical Conditions in the Elderly:Impact on Pharyngeal Bolus Transit

Deglutition in the elderly may be impacted by the sequelae of medical diseases. It is unknown if the long-term presence of common medical diseases, such as arthritis and hypertension, leads to changes in neurologic and muscular function and thus swallowing ability. The aim of this project was to determine if the duration of bolus pharyngeal transit in nondysphagic elderly individuals with chronic medical problems is longer than that measured in nondysphagic elderly individuals without medical problems. Videofluoroscopic swallowing studies were performed on 63 elderly subjects with a variety of well-controlled medical problems and on 23 elderly subjects with no medical problems. The mean timing of pharyngeal bolus transit was compared between the two groups. The relationship between the presence of medical problems and the likelihood of transit times prolonged beyond two standard deviations of the mean transit time found in 60 younger normal controls was also analyzed. Findings included significantly prolonged pharyngeal transit time in the group of subjects with medical problems compared with those subjects without medical problems for a small bolus size. Those individuals with hypertension demonstrated the most significant delays in bolus transit. The presence of medical problems did correlate with an increased likelihood of prolonged transit times. This preliminary study indicates that medical problems common in elderly populations are associated with a deterioration of swallowing function and that changes identified in elderly individuals may not be due to aging alone.     

Dysphagia in Progressive Supranuclear Palsy: Radiologic Features

Progressive supranuclear palsy (PSP) is a progressive degenerative extrapyramidal disease that often masquerades as Parkinson's disease (PD). Similar to PD, dysphagia frequently complicates the course of PSP. Because there is only one published report characterizing dysphagia in PSP, we reviewed the neurologic features and dynamic videofluoroscopic swallowing function study results in 10 dysphagic PSP patients. Abnormalities during multiple stages of ingestion were recorded in each patient. Uncoordinated lingual movements, absent velar retraction or elevation, impaired posterior lingual displacement, and copious pharyngeal secretions were noted in all patients. Tongue-assisted mastication, noncohesive lingual transfer, excessive oral bolus lingual leakage to the pharynx prior to active transfer, vallecular bolus retention, abnormal epiglottic positioning, and hiatal hernias were noted in at least half of the cohort. Although ingestion abnormalities in PSP are similar to those previously reported in PD, the number of studied patients and observed differences were too few to clearly differentiate the two diseases.     

Change in Levator Veli Palatini Muscle Activity in Relation to Swallowing Volume During the Transition from the Oral Phase to Pharyngeal Phase

The aim of this study was to examine whether the levator veli palatini (LVP) muscle might be involved in the regulation of velopharyngeal function during the transition between the oral and pharyngeal phases during swallowing, and to examine whether LVP muscle activity could be regulated in relation to the volume of swallowing. Eight normal adults participated in this study. Smoothed EMG signals of the LVP muscle were collected. At the same time, palatoglossus muscle activity was also monitored. Each subject swallowed water at five different volumes: 12.5%, 25%, 50%, 100%, and 150 (or 200) % of the optimum volume for swallowing, which was individually determined for each subject. LVP muscle activity was positively correlated with changes in swallowing volume. The LVP muscle was involved in the regulation of swallowing during the transition from the oral to pharyngeal phases.This research was supported by a Grant-in-Aid for Scientific Research [(B) No. 16300237, (C) No. 16639020, No.15592048, No.17592021) from the Ministry of Education, Science, Sports and Culture, Japan.     

A Scintigraphic Study of Oral, Pharyngeal, and Esophageal Transit in Patients with Stroke

Although stroke affects mainly the oral and pharyngeal phases of swallowing, it may also impair esophageal contractions. Our hypothesis is that stroke may affect esophageal transit. The oral, pharyngeal, and esophageal transit was studied by the scintigraphic method in 26 patients (age range=26-83 years), eight of whom had mild dysphagia but all were able to feed orally and who had suffered an acute first-ever ischemic stroke 10-56 days (median = 43 days) before transit evaluation. The control group included 15 healthy volunteers (age range=27-86 years). All subjects swallowed a 5-ml liquid bolus and a 5-ml paste bolus labeled with technetium-99m phytate while sitting in front of the collimator of a gamma camara. The oral, pharyngeal, and proximal, middle, and distal esophageal transit was measured for 20 s. Three patients did not swallow the bolus during the scintigraphic evaluation. There was no difference between patients and controls with respect to oral and pharyngeal transit or clearance of liquid. For paste, the pharyngeal transit time was shorter for patients (0.48+/-0.17 s) than for controls (0.61+/-0.18 s, p=0.027). Also for the paste bolus, the residue in the mouth was greater in patients (18.4+/-13.6%) than in controls (10.2+/-4.9%, p=0.031). The liquid transit duration in the distal esophagus was shorter in patients with stroke (1.74+/-0.84 s) than in controls (2.68+/-1.65 s, p=0.028). There was no difference between patients and controls in esophageal residue. In conclusion, patients with stroke and able to feed orally may have alterations in the esophageal transit of a liquid bolus.     

Sequence Variability During Hypopharyngeal Bolus Transit

The pharyngeal phase of deglutition is considered to occur in a reflexive, preprogrammed fashion. Previous studies have determined a general sequence of events based on the mean timing of bolus transit and swallowing gestures. Individual variability has not been studied, however. The purpose of this study was to determine the amount of sequence variability that normally occurs during the hypopharyngeal phase of deglutition. Dynamic swallow studies from 60 normal volunteers were evaluated and event sequence variability was determined for 12 two-event sequences during swallowing of three bolus sizes. There was found to be some variability in event sequences for almost all events evaluated except for the following : (1) arytenoid cartilage elevation always began prior to opening of the upper esophageal sphincter, (2) the sphincter always opened prior to the arrival of the bolus at the sphincter, (3) larynx-to-hyoid approximation always occurred after the onset of upper esophageal sphincter opening, and (4) maximum pharyngeal constriction always occurred after maximal distension of the upper esophageal sphincter. Variability was more common during swallowing of the smallest bolus size. This information may be helpful in evaluating event coordination in patients with dysphagia.     

Use of Fiberoptic Endoscopic Evaluation of Swallowing (FEES) in Patients with Amyotrophic Lateral Sclerosis

This study investigated the use of fiberoptic endoscopic evaluation of swallowing (FEES) to both diagnose pharyngeal dysphagia and make treatment recommendations in 17 consecutive patients with a new diagnosis of amyotrophic lateral sclerosis (ALS) and complaints of dysphagia. Ten of 17 (59%) patients exhibited pharyngeal dysphagia with aspiration or aspiration risk with clear liquids, i.e., 5 of 8 (63%) limb and 5 of 9 (56%) bulbar. If depth of bolus flow was a problem, thickened liquids and single, small bolus sizes were recommended. If bolus retention was a problem, a small clear liquid bolus after each puree or solid bolus was recommended to aid pharyngeal clearing. Five of 17 (30%) patients required multiple FEES evaluations because of disease progression. For the first time in patients with ALS, FEES was shown to be successful in assessing preswallow anatomy and physiology, diagnosing pharyngeal dysphagia, and providing objective data for appropriate therapeutic interventions to promote safer oral intake. Visual biofeedback provided by FEES was successful for both patient and family education and to investigate individualized therapeutic strategies that, if successful, can be implemented immediately. Serial FEES allows for objective monitoring of dysphagia symptoms and timely implementation of diet changes and/or therapeutic strategies to continue safer oral intake and maintain optimum quality of life.This research was supported, in part, by the McFadden, Harmon, and Mirikitani Endowments.     

Dysphagia after pharyngolaryngeal cancer surgery. Part I: Pathophysiology of postsurgical deglutition

Eighty-one patients were examined after laryngopharyngeal cancer surgery with a sequential computer manometry system using 4-channel-pressure probes. The general swallowing coordination is neither a matter of the oropharyngeal pressure thrust nor of the pharyngeal transit time, but mainly depends on swallowing initiation. The points of interest are both the pharyngeal inlet and outlet. The topographic correlates are the base of the tongue and the upper esophageal sphincter (UES). Resections of the base of the tongue lead to a decrease of volume available for pressure generation, thus reducing the tongue driving force. The swallowing reflex is uncoordinated resulting in dyskinesia of the UES. Compensation may be achieved with a stronger oropharyngeal thrust and/or repeated swallows. Distal resections alter the pharyngoesophageal segment so that a functional obstruction results, combined with lower pressure amplitudes in the hypopharynx, reducing the pressure gradient necessary for bolus flow. This increasing resistance can be overcome by higher propulsive forces in the base of the tongue region. In case of additional lingual defects, deglutition is subject to decompensation, highlighting the major role of the tongue as a pressure generator for bolus passage.     

Evaluating Oral Stimulation as a Treatment for Dysphagia after Stroke

Deglutitive aspiration is common after stroke and can have devastating consequences. While the application of oral sensory stimulation as a treatment for dysphagia remains controversial, data from our laboratory have suggested that it may increase corticobulbar excitability, which in previous work was correlated with swallowing recovery after stroke. Our study assessed the effects of oral stimulation at the faucial pillar on measures of swallowing and aspiration in patients with dysphagic stroke. Swallowing was assessed before and 60 min after 0.2-Hz electrical or sham stimulation in 16 stroke patients (12 male, mean age = 73 ± 12 years). Swallowing measures included laryngeal closure (initiation and duration) and pharyngeal transit time, taken from digitally acquired videofluoroscopy. Aspiration severity was assessed using a validated penetration-aspiration scale. Preintervention, the initiation of laryngeal closure, was delayed in both groups, occurring 0.66 ± 0.17 s after the bolus arrived at the hypopharynx. The larynx was closed for 0.79 ± 0.07 s and pharyngeal transit time was 0.94 ± 0.06 s. Baseline swallowing measures and aspiration severity were similar between groups (stimulation: 24.9 ± 3.01; sham: 24.9 ± 3.3, p = 0.2). Compared with baseline, no change was observed in the speed of laryngeal elevation, pharyngeal transit time, or aspiration severity within subjects or between groups for either active or sham stimulation. Our study found no evidence for functional change in swallow physiology after faucial pillar stimulation in dysphagic stroke. Therefore, with the parameters used in this study, oral stimulation does not offer an effective treatment for poststroke patients.Abbreviations: mA = milliamps; FP = faucial pillar; LCD = laryngeal closure duration; OTT = oral transit time; PTT = pharyngeal transit time; SRT = swallow response time; TMS = transcranial magnetic stimulation; UES = upper esophageal sphincter.     

The Prediction of Persistent Dysphagia Beyond Six Months After Stroke

The purpose of this study was to identify the videofluoroscopic prognostic factors that affect the recovery of swallowing function at an early stage after stroke and to make a tool for predicting the long-term prognosis. Eighty-three poststroke patients were selected prospectively. These patients had all undergone videofluoroscopic swallowing studies at an average of 40 days after stroke onset and were followed up for over six months. Prognostic factors were determined by logistic regression analysis between the baseline videofluoroscopic findings and aspiration over six months (p < 0.05). A videofluoroscopic dysphagia scale (VDS) with a sum of 100 was made according to the odds ratios of prognostic factors. The validity of the scale was evaluated by using a receiver operating characteristic curve. The VDS was compiled using the following 14 items: lip closure, bolus formation, mastication, apraxia, tongue-to-palate contact, premature bolus loss, oral transit time, triggering of pharyngeal swallow, vallecular residue, laryngeal elevation, pyriform sinus residue, coating of pharyngeal wall, pharyngeal transit time, and aspiration. At a scale cutoff value of 47, the sensitivity was 0.91 and the specificity was 0.92. The VDS was developed to be used as an objective and quantifiable predictor of long-term persistent dysphagia after stroke.     

Oral and Pharyngeal Transit of a Paste Bolus in Chagas’ Disease

We measured the oral and pharyngeal transit of a paste bolus in 20 patients with Chagas' disease and 21 controls. Each subject swallowed of a 10-ml paste bolus prepared with 50 ml of water and 4.5 g of instant food thickener labeled with 55.5 MBq of 99m technetium phytate. After the scintigraphic recording of the transit, we delineated regions of interest (ROI) corresponding to mouth, pharynx, and proximal esophagus. Time-activity curves were generated for each ROI. There was no difference between patients with Chagas' disease and controls with respect to the duration of oral and pharyngeal transit, amount of pharyngeal residue, or flux of bolus entry into the proximal esophagus. The amount of oral residue was higher in patients with Chagas' disease (median = 0.71 ml) than in controls (median = 0.45 ml). The pharyngeal clearance duration was longer in patients with Chagas' disease (median = 0.85 s) than in controls (median = 0.60 s). The oral transit duration of the patients with Chagas' disease and dysphagia (median = 0.55 s, n = 14) was shorter than the oral transit duration of chagasic patients without dysphagia (median = 0.80 s, n = 6). We conclude that when swallowing a paste bolus, patients with Chagas' disease may have an increased amount of oral residue and a longer pharyngeal clearance duration than asymptomatic volunteers.     

Oropharyngeal Scintigraphy: A Reliable Technique for the Quantitative Evaluation of Oral–Pharyngeal Swallowing

A valid and reliable technique to quantify the efficiency of the oral–pharyngeal phase of swallowing is needed to measure objectively the severity of dysphagia and longitudinal changes in swallowing in response to intervention. The objective of this study was to develop and validate a scintigraphic technique to quantify the efficiency of bolus clearance during the oral–pharyngeal swallow and assess its diagnostic accuracy. To accomplish this, postswallow oral and pharyngeal counts of residual for technetium-labeled 5- and 10-ml water boluses and regional transit times were measured in 3 separate healthy control groups and in a group of patients with proven oral–pharyngeal dysphagia. Repeat measures were obtained in one group of aged (> 55yr) controls to establish test–retest reliability. Scintigraphic transit measures were validated by comparison with radiographic temporal measures. Scintigraphic measures in those with proven dysphagia were compared with radiographic classification of oral vs. pharyngeal dysfunction to establish their diagnostic accuracy. We found that oral (p = 0.04), but not pharyngeal, isotope clearance is swallowed bolus-dependently. Scintigraphic transit times do not differ from times derived radiographically. All scintigraphic measures have extremely good test–retest reliability. The mean difference between test and retest for oral residual was –1% (95% CI –3%–1%) and for pharyngeal residual it was –2% (95% CI –5%–1%). Scintigraphic transit times have very poor diagnostic accuracy for regional dysfunction. Abnormal oral and pharyngeal residuals have positive predictive values of 100% and 92%, respectively, for regional dysfunction. We conclude that oral–pharyngeal scintigraphic clearance is highly reliable, bolus volume-dependent, and has a high predictive value for regional dysfunction. It may prove useful in assessment of dysphagia severity and longitudinal change.     

Hyoid-Bolus Transit Latencies in Normal Swallow

Pharyngeal swallow delay is frequently found in dysphagic patients and is thought to be a factor in a range of swallowing problems, including aspiration. Implicit in notions of swallow “delay” is a temporal interval between two events that is longer than normal. However, there appears to be little agreement about which referent events should be considered in determining delay. A number of pharyngeal bolus transit points and various pharyngeal gestures have been used in delays determined from fluoroscopic evidence, and other referents have been used in electromyographic and manometric studies of swallow. In this study latencies between the first movement of the hyoid and several pharyngeal bolus transit points were calculated from fluoroscopic swallow studies in normal nondysphagic adults. Means and standard deviations of these latencies are provided for a 3-cc and a 20-cc bolus and for both nonelderly and elderly adults. The data may be a useful resource for relating the specific latencies investigated to concepts of pharyngeal swallow delay, in particular, when assessing videofluoroscopic studies using a similar protocol.     

Effects of Bolus Consistency on Timing and Safety of Swallow in Patients with Parkinson’s Disease

Aspiration pneumonia is the leading cause of death in Parkinson’s disease (PD) patients. In clinical practice, the videofluoroscopic examination (VFE) is the most common method for evaluation of swallowing disorders. One of the variables manipulated during the VFE is consistency of the bolus. The results of this examination greatly influence the recommendations made by speech-language pathologists regarding swallow therapy and/or intervention. The primary aim of this study was to investigate the effects of bolus consistency on penetration-aspiration (P-A) score and timing of swallow of persons with PD. The videoradiographic images of ten participants with PD swallowing six thin and six pudding-thick boluses were analyzed. Swallow timing and P-A were measured. (i.e., oral transit time, pharyngeal transit time, number of tongue pumps, and P-A score). The results demonstrated various significant differences and relationships among the dependent variables. Implications for further research and clinical practice are discussed.     

Dysphagia following Anterior Cervical Spine Surgery

Although previous reports have identified dysphagia as a potential complication of anterior cervical spine surgery (ACSS), current understanding of the nature and etiologies of ACSS-related dysphagia remains limited. The present study was undertaken to describe the patterns of dysphagia that may occur following ACSS. Thirteen patients who exhibited new-onset dysphagia following ACSS were studied retrospectively by means of chart review and videofluoroscopic swallow study analysis. Results indicated that a variety of swallowing impairments occurred following ACSS. In 2 patients, prevertebral soft tissue swelling near the surgical site, deficient posterior pharyngeal wall movement, and impaired upper esophageal sphincter opening were the most salient videofluoroscopic findings. In another 5 patients, the pharyngeal phase of swallowing was absent or very weak, with resulting aspiration in 3 cases. In contrast, an additional 4 patients exhibited deficits primarily of the oral preparatory and oral stages of swallowing including deficient bolus formation and reduced tongue propulsive action. Finally, 2 patients exhibited impaired oral preparatory and oral phases, a weak pharyngeal swallow, as well as prevertebral swelling. Thus, a variety of swallowing deficits, due possibly to neurological and/or soft tissue injuries, may occur following ACSS.     

The Effects of Cervical Bracing Upon Swallowing in Young,Normal, Healthy Volunteers

Abstract The purpose of this study was to evaluate radiographically the effects of cervical bracing upon swallowing thin liquids and solid food in normal adults under three cervical bracing conditions. This was a prospective, repeated measures design study. Seventeen healthy adult volunteers between the ages of 30 and 50 were recruited from hospital staff. All subjects reported no previous history of swallowing difficulty or diseases that might affect swallowing. Subjects were radiographically observed swallowing thin liquids and solid food without cervical bracing and with three common cervical orthoses (Philadelphia collar, SOMI, and halo-vest brace). Order of bracing and type of bolus were randomized. Changes in swallowing function (point of initiation of swallow response, presence of pharyngeal residue, airway penetration, hyoid bone movement, diameter of oropharyngeal airway, and durational measurements) were analyzed by two independent raters. Eighty-two percent (14/17) of the subjects demonstrated radiographic changes under one or more of the bracing conditions. Forty-seven percent (8/17) of subjects demonstrated changes with point of initiation of the swallow response, 59% (10/17) demonstrated increased pharyngeal residue, and 23.5% (4/17) demonstrated changes with bolus flow with laryngeal penetration present. Aspiration did not occur under any of the bracing conditions. Changes noted in durational measurements for oral containment and total pharyngeal transit under the bracing conditions were not considered statistically significant. This study shows that cervical bracing does change swallowing physiology in normal healthy adults.